Two-way electrical communication system



Sept. 20, 1938.

c. L. CALKINS TWO-WAY ELECTRICAL COMMUNICATION SYSTEM Filed March 16, 1954 8 Sheets-Shee t l 17? W??? Z 07 (Zawev'gyj fa/ zzw Sept, 20, 1938.,

c. L. CALKINS TWO-WAYELECTRICAL COMMUNICATION SYSTEM K Fi led March 16, 1934 a Sheets-Sheet 3 PM... E

Sept. 20, 1938. L. C LK 2,1303% TWO-WAY ELECTRICAL COMMUNICATION SYSTEM Filed March 16, 1934 8 Sheets-Sheet 3 f2? z/ezzzaz" 6%azzzrazyj $55225 -5 MIM Jtfarneym Sept. 20, 1938. c. L. CALKINS I TWO-WAY ELECTRICAL COMMUNICATION SYSTEM Filed March 16, 1934 8 Sheets-Sheet 4 p Ewe c. L. cALKiNs TWO-WAY ELECTRICAL COMMUNICATION SYSTEM Filed March 16, 1934 8 Sheets-Sheet 5 EVOQJ firllllllllllllll II II c. n... @ALKENS 2,1303% Two-my ELECTRICAL COMMUNICATION SYSTEM 8 Sheets-Sheet 6 Filed March 16 1934 [72 7/872 Z07" Ckazuzce .lttarneys TWO-WA; ELECTRICAL COMMUNICATION SYSTEM Filed March 16, 1934 8 Sheets-Sheet 8 Patented Sept. 20, 1938 UNITED STATES TWO-WAY ELECTRICAL COMlVIUNICATION SYSTEM Chauncey L. Calkins, Chicago, Ill., assignor to Lothar A. Edcrer, Chicago, Ill.

Application March 16,

3 Claims.

My invention relates to improvements in means and apparatus for two-way electric communication, and in one form to semi-automatic two-way message transmitting equipment, and may especially be adapted for communicating systems, such as are required in factory production control,

One object of my invention is to provide an apparatus capable of transmitting relative complex messages in a semi-automatic manner. Another object of my invention is to provide apparatus that may be operated by persons entirely unskilled in the use of telegraphic apparatus. Another object of my invention is to provide a simple apparatus for such intercommunication as is required in factory control of interdepartmental service, by which an almost unlimited variety of simple messages may be rapidly exchanged.

For the purpose of illustrating my invention, I

have shown a complete workable apparatus including various structural details, and I have also shown a schematic wiring diagram of such complete two-way intercommunicating circuit.

It will be understood that these parts may take other forms than those shown and that the circuit arrangement may be in other forms than that shown, and still accomplish the same purpose in the same manner. Hence, the showing here made is to be considered as in a sense diagrammatic.

Fig. 1 is-a front elevation of a two-position central switchboard and recorder units;

Fig. 2 is a section along the line 2--2 of Fig. 1;

Fig. 3 is a perspective .view of the metallic framework construction of such a board;

Fig. 4 is a detail of a recorder unit bank, with parts omitted, used in the board shown in Fig. 1;

Fig. 5 is a Vertical section along the line 5-5 of Fig. 4, illustrating the reset magnet for an individual indicator used in the recorder unit bank;

Fig. 6 is an enlarged section along the line 6-6 of Fig. 4, illustrating the set-up mechanism of such indicator;

Fig. '7 is another sectional view of such indicator, taken along the line l-l of Fig. 9;

Fig. 8 is a section along the line 8-8 of Fig. 7, showing the method of attachment of such indicator unit to the frame;

Fig. 9 is a section along the line 9-9 of Fig. 4;

Fig. 10 is an enlarged section along the line iii-4i! of Fig. 4, illustrating the step-up switch and the method of connecting electrical circuits;

1934, Serial 1%. 715,904

Fig. 11 is a sectional view through line ll--|l of Fig. 10;

Fig. 12 is a sectional view along the line |2-l2 of Fig. 9;

Fig. 13 is an enlarged section of the step-up switch along the line i3l3 of Fig. 11;

Fig. 14 is a schematic wiring diagram of the circuit;

, Fig. 15 is an across-the-line diagram of the circuits comprising the system.

Like characters indicate like parts throughout the specification and drawings. For the sake of clarity, in describing the electrical circuit and system, designation has been chosen in which sub-assemblies are given capital letters, and elements in each sub-assembly small letters of corresponding character with appropriate superscripts, and the wiring designated by figures.

Referring to Fig. 1, A is a casing or cabinet carrying a plurality of slotted, visual indicator housings B. C and C are automatic impulse generating dials, and C C C are a group of transfer or reset switches associated with dial C. (2 C C are a group oftransfer or reset switches associated with dial C C is a main power switch. C is a lock type buzzer switch. D, D, D are; three jack plugs carried on flexible cables and associated with dial C D D D are another set of three jack plugs, carried on flexible cables and associated with dial C. E, E and E and also E E are groups of signal lamp lenses.

Referring to Fig. 2, D, D, D are jack plugs attached to flexible cables d, d, d. C is an indicating dial. A indicates a housing or cabinet. at and a 'indicate vertical metallic cabinet supporting members. a a indicate horizontal metallic cabinet supporting members. a a indicate metallic cross bracing. a a indicate horizontal metallic shelf members, which together with members a and at forms a front shelf or horizontal apron. a' a' are angularly disposed metallic supports adapted to carry relatively heavy groups of recorder unit banks B a a c are metallic framework members of the extended vertical portion of the members carrying otherrelatively heavy assemblies. a is a line terminal group for attachment of interior electric wiring and its connection with external electrical circuits and wiring,

Referring to Fig. 3, in addition to members already described in Fig. 2, here shown in perspective, the following cross members appear; a a shelf cross bar, a upper bank cross bar, and e 3, a a horizontal, panel cross members,

carrying two small sockets Z9 12 also special bracing member a attached only to the central shelf supporting member at. The cross bar (L12 and the adjacent bank cross bar a may be connected by vertical members 0,

Referring to Fig. 4, B is a recorder unit bank adapted to carry 12 indicator units G. These indicators are mounted and positioned in slotted bar 27 and upon the slotted positioning bar I2 which are secured to the end plates Z7 to form cradles adapted as a whole to be mounted upon the supports a'. Electrical connections are made from the indicator units G to a series of insulated plugs b", each carrying three terminal sockets Z1 Z2 and 19 To provide for certain common Wiring, an insulated plug b is provided 11 is a reset magnet. 21 is a supervisory lamp receptacle and bracket. F is a step-up switch unit, which sub-assembly is generally similar to indicator units and is similarly mounted along with the indicator units in the general bank frame B.

Referring to Fig. 5, g is a signal lamp associated with each recorder unit bank and in phantom is shown in corresponding sight glass or opal E 12 is the reset magnet which actuates the reset rod 12 and associated fingers I9 The magnet b is by means of its frame g mounted together with the signal lamp upon one of the end plates Z9 g is an indicator unit frame plate upon which is mounted a shaft 9 carrying an indicator drum shown in Fig. 4 as g. Upon this shaft is mounted a ratchet wheel g' actuated by the pawl 9 The pawl is carried upon a compound lever comprising the member 9 pivotally attached to member 9 Member 9 is rounded for rolling contact at the end opposite the pawl carrying end. Its rounded face is adapted to engage a fulcrum plate g projecting from the plate g The ratchet is held against return motion by stop o which stop is pressed against the ratchet by means of the spring 9!. Spring 913 normally holds the pawl g into engaging position with the ratchet wheel and at the same time retains the rounded end of the lever g in engagement with the fulcrum plate $7 9. The compound lever is mounted on a shaft 57 which in turn is. driven byits operating magnet Q Referring to Fig. '7, g is an indicator drum attached to the step-up mechanism of the indicator unit. Upon this drum is a cam g adapted to engage insulated button g upon the spring switch 'leaf g. Q is a pair of electrical switch contacts carried upon spring leaves g and 9 Referring now to Fig. 8, the end plate 11 and the slotted support bar b are clearly shown. The ratchet and pawl mechanism together with the operating magnet appear clearly in side View, g being the magnet, g the armature, and main lever upon which is pivoted the rolling contact lever g carrying the pawl g which acts upon the ratchet wheel 9''.

Referring to Fig. 9, a spring member g is a return spring rigidly attached at one end to the plate 9 mounted upon the fixed shaft g and at the other to the rotatable drum 9 which spring resists stepping up motion of the drum by the pawl mechanism and which returns the drum to normal position when the stop Q11 is released.

Referring to Figs. 10, 11 and 13, F is an advance unit or step-up switch carried upon a frame plate f, operated by a magnet I having an armature and acting upon a compound lever similar in all respects to that of the indicator unit. f is a switch contact housing cover.

I is the insulated switch contact block carrying a series of switch contacts f I I is a common contact wiper ring having an electric con nection attached thereto leading to the switch terminals. The switch contact block is rigidly mounted upon the stud or pin 1". Upon this stud or pin is the step-up mechanism f of a form generally used. It is a spring returnable by means of the spiral spring I". This step-up mechanism carries upon its end the flexible spring wiper f which contacts the switch buttons f and the flexible wiper i which wipes the ring contact i Referring to Fig. 12, the detailed construction of the drum with its mounting, drive and return means are clearly shown. g is the character bearing drum, 9 the ratchet wheel attached to the drum but free to rotate on the stud 9 g is the return spring plate and Q31 the spring.

Referring to Fig. 14, H, H are impulse generating units similar to the automatic dial of the dial telephone. They contain impulse generating cams h, impulse switch points h special impulse generator h and the off normal switch h operated by the special arm h*. J and J are two indicator banks comprising the individual indicator units 7', 7' 7' 7' 7' and 7' in the bank J, and i 1' 7' 7' and 7 etc. in the bank J K and K are step-up switch units associated with the indicator banks J, J The step-up switch units'contain switches carrying the arms k, H, which pass over the series of contacts 70 k 70 7e I0 and 70 in unit K, and It, 1e la is, 70 and k in unit K L and L are reset magnetic trips for the indicator banks and the step-up switch units of each group. M and M are bell signals associated with each group. m, m and m are signal lamps associated with each group. N is a battery supplying power to the system. '0 is a transfer or reset switch located at the central station carrying the con-' individual contacts p, p and 13 Q is one of a series of line jacks at the central station Q indicating a second such line jack connected to another sub-station not shown. Theline jack Q has the individual contact leaves or points q, q (1 q and 11 R is a reset button at a substation. It has the contact points r. S is a call button located at a sub-station. It has the contact points 8. T is a call relay having the magnet i, and the contact points t t U is a return, call relay having the compound winding u, u and the contact points 11, and 11. V is a spark suppressing condenser bank. 11 v are a spark suppressing condenser and resistance. 0 o and v are a spark suppressing assembly including condensers and resistance. The wiring connecting the 'various parts of the apparatus will be fully described in the discussion of the use and operation of the invention.

The use and operation of my invention are as follows:

a A central station is provided which may accommodate any desired number of operators, the number depending in turn upon the number of sub-stations, which each operator is able to handle in normal traffic. In the particular form shown, a single board is shown which may accommodate twooperators, or may, in certain cases, be operated by one person. This board is capable of receiving messages from a plurality of substation dispatchers. Since the handling of messages is identical in all cases for all sub-station station is calling.

central station. The sub-station dispatchers may be disposed, for example, throughout a fac- I tory, one placed near each machine, and the central station may be located in the superintendents ofiice. A workman, then, may wish to transmit the information that his machine has stopped for one reason or another, that he requires a certain part, or that herequires certain service or that a certain job is finished. To place such a call, he'depresses the call button S upon his sub-station dispatcher. Wire l is the main negative lead and wire 2 the main positive lead. Negative connection is made to the call button S from the negative side of the battery N through the main negative power lead I. Positive connection exists from the positive side of the battery N through the wire 2 through the signal lamp m and further through wire 2 through the cable X, to the winding u of the tandem wound relay U, from this relay to and through the wire 3 to the relay T, and through wire 4 from the relay T to the contact 8 of the call button S. Closure of this switch then will cause lamp m to glow and this lamp being located upon the switchboard ofthe central station will indicate to the central station operator that a certain sub- The establishment of the circuit energizes the relay T, closing the contacts t and 15 The closure of contact it places that side of the relay T in negative connection and holds this relay energized. This contact also will then hold the relay U locked in position with contacts a closed and contacts a open. The closure of contact t makes negative connection through the wire 5 to one side of the signal lamp m and aljsoto one side of the buzzer M, which may be out out by the switch M The other sides are connected to the positive side of the battery N by the positive power wire 9, hence the signal lamp m and the audible signal M register, calling the operators attention to the fact that a signal is being sent. The central station operator, having been signalled, places the'plug P in its appropriate line jack Q to answerthe call. The independent electrical connections are thereby made, the contact point p of the plug is in engagement with the contact member q the contact member 71 engages the member q and the con tact p of the plug P is in engagement with the member q; further the contact members (1 and q are closed indirectly. This causes the supervisory lamp m of the sub-station to glow, indicating that the operator of the central switchboard is now ready for a message. Electrical connections are made from the battery N, through positive wire 2, contact members q*, (1 line l5, wire it to the supervisory lamp m thence through the line I i and negative line I back to the battery. Another electrical circuit is established from the battery N, positive wire 2, contact members 11 (1 line l5, through the winding u of thetandem relay U, the contact points 11?, and wire I back tothe negative pole of the battery. This electrical circuit locks the tandem wound relay U which had been energized by the winding u previously described. However, it will be realized that as soon as the central switchboard operator inserts the plug P into the line jack Q the relay U will be energized by means or the winding a regardless of whether the Winding u is energized hereafter or not. The purpose'or energizing and locking the tandem wound relay is to keep the contactswitch a separated which consequently prevents sounding of the buzzer or signal device M which is shunted across the line 15" and negative line i by the wires 26 and interposed switch u The workman may now dial his message, and in so doing as soon as the dial H is moved ofi the normal position, the arms 7& and h are moved away from their respective switch points, allowing the switch points It to close and to remain so until the dial returns to its normal position, as illustrated in Figure 14. Closing of the switch points 11 establishes an electrical circuit through the electro-magnet k of the step-up unit K and the electro-magnet k of the advance unit K which by means of the ratchet wheels W, k and associated actuating means instantly rotate the commutator switch arms k and k" clockwise, referring to the position in which they are shown in Figure 14. The switch arm k then rests upon the contact k and the switch arm k of the step-up unit K then rests upon the contact 70 The electrical circuits for the step-up units are from the battery N through the positive wire 2, contact points q"*, q of the line jack Q, wire it), wire I3 and wire 12, switch points 71. line it to the step-up unit magnet 70 of the substation dispatcher, which is connected to the negative-wire 1 leading to the negative pole of the battery. Likewise the shunt wire in is in electrical connection with the switch member 71 delivering electrical current through the contact member q of the line jack Q, contact member 31 of the plug P, wire H! to the electro-magnet k of the step-up unit K which is connected to the negative wire I completing the circuit to the negative pole of the battery. A spark suppressing condenser bank is placed upon one side of this circuit for the purpose of suppressing sparks at the impulsing contacts. The electrical connections established by the wiper arms 7c, 70 of the step-up units K, K then places the indicator 6 in operating connection through units a and y the wires 20 and 2!, the far side of the operating C f.

magnets being connected to main negativelead l L Then, as impulse generator H is manipulated by means of the cam 11, impulses generated will be sent as theresult of the movements of the contact leaves tact 76 of the step-up unit K and the wire 2!! to the indicator 1' and also through the wire 36, the line jack q and contact p and wire 3| to the arm 70 of the step-up unit K, and thence through wire 2| into the indicator 7'. quently, both these indicators will simultaneously receive a series of impulses dependent upon the manipulation of the dial of the impulser. These indicators will then be stepped up so that their drum faces will show character corresponding to the character dialed or determined by the manipulation of the impulser 1-1 This, then, shows to both the transmitting and receiving operators simultaneously the first character of the message which may be any simple number or letter of a group of 5, l0, 15, depending upon the constructionof the impulser and its dial. Upon return of the dial of the impulser H to neutral position, the contact 72 is opened. This de-energizes the magnets 70 and k of the respective step-up switch units, preparing these units for a further step-up. Upon the next motion of the dial of the impulser H this contact 71 will close and h through the wire ll, the con- Conse- 25,-;

its

switch units, as in the previous case. This secnd impulse will cause a second step-up of the respective units simultaneously, placing the arms upon the secondv contacts 10 and k of the stepup units, and consequently bringing indicators :i and i into operating position. These indicators then respond to impulses sent out by the second manipulation of the dial and impulser H registering simultaneously for both transmitter and receiver the second'character of the message, which may also be in one of a designated group of simple characters. This procedure is continued until the message is complete, which may extend, in the case of the drawings shown, to 6 characters. It is, of course, obvious that a greater number of indicators, and consequently a greater number of characters, may be used, andrthat a greater number of character positions may be provided permitting longer messages. In other words, the system is not to be construed as being confined to any specific number of characters or character positions.

It will be noted that in the central station, upon the functioning of any indicator, the contact i associated with it will close, and that upon closing, this completes a circuit from the positive side of the battery through wire 9 through the supervisory lamp m thence through the contact 1' and into the main negative lead 1. This supervisory lamp indicates that one or more indicators are off normal. There are a similar set of contacts associated with the indicators upon the sub-station dispatcher which do not, however, perform a like function. These contacts make negative connection from main negative lead I through contact of any particular indicator and the wires 22 and 3 to-the call relay T, cutting this relay out, causing its contacts to open, thus disconnecting buzzer M upon the central switchboard and the lamp 122. The closing of any contact 7' establishing negative connection through the wire 22, will, however, keep relay U energized through the winding it since there is a positive connection from the other side of this winding through wire 2. This relay remaining closed, the lamp m indicating to the central station operator the station calling, re-

mains lighted. The indicator units upon both systems may be cleared after the central station operator has received the message satisfactorily by throwing a key switch 0. In the construction shown in the drawings, this key switch is thrown to the left, which is a non-locking position. This operation closes the contact members 0 o and makes negative contactdirectly to the reset magnet L through the'wires 23 and 24, and alsothrough the continuation of wire 24to the contacts p and q thence into wire 1 l to the reset magnet L which receives positive current through the wires l3, l5, switch contacts (1 q and positive wire 2 from the battery N.

Should the workman desire to clear the indicators upon both the transmitter and receiver, as for example, in the case of error made, he depresses the reset button R, which has an action similar to the throwing of the switch 0 in that negative connection is made from main negative lead I, through contact r to wire 25 and thence to wire H, which is connected toone side of the reset magnet L and through contacts q and p of the plug P and wires 24 and 23 in similar position with respect to the magnet L. These magnets having then negative connection upon one side, are energized since positive connection is made through wires l3 and I5, the contacts q q and the main positive power wire 2. Should the central station operator wish to signal the sub-station operator, the operator merely inserts the plug P into the appropriate line jack Q. This closes the contacts q :1 and makes positive connection through to wire I through wire 26 with the interposed contact W, to the buzzer M which sounds. Upon the sounding of the buzzer the workman responds by depressing the call button S in the same manner as though he were signalling the central station operator. The pressing of the call button S makes connections already described and puts the apparatus into position for transmission. Central station operator has a dial H similar in all respects to the dial H To operate this dial as a sender, the operator throws the switch 0 into a locking position which in the showing of Fig. 14, is to the right. This places the contacts h of the impulser into communication with the element p of the plug through the contacts 0 of the switch and also places the contacts 71 of the impulser into communication with the element p of the plug. These two elements complete the circuit as already described, which permits impulses to be transmitted simultaneously toboth banks of indicators.

' I claim:

1. In a message transmitting system, a calling station including means for sending a message, a receiving station including means forindicating a message received, means operatively connecting the calling station and the receiving station, and the respective message sending means and the message indicating means,,whereby messages sent from the calling station are received and indicated at the receiving station, message indicating means at the calling station, said message indicating mechanism at the calling station including a part movable in response tothe dispatch of a message, a signal at the receiving station, means for energizing the signal from the calling station, and means responsive to movement of said movable part of the message indicator at the calling station for deenergizing said signal.

2. In a message transmitting system, a calling station including means for sending a message, and indicating means for indicating a message sent, a receiving station including means for indicating the receipt-of a message from the calling station, means operatively connecting the mes sage sending mechanism and the message indicating mechanism of the respective stations for the transmission and receipt of messages; a signalilocated at the receiving station, a circuit for energizing said signal, means for energizing said circuit from the calling station, said message indicating means at the calling station including a part movable in response to the dispatch of a message from the calling station, said signal energizing circuit including switch means located at the calling station, and means operable in response to movement of said movable part of the indicating mechanism for opening said switch to deenergize the signal upon receipt of a message from the calling station.

3. In a message transmitting system, a calling station including means for sending a message and means for indicating a message sent, a receiving station including means for indicating a message received, means operatively connecting the calling station and the receiving station and the respective message sending means and the message indicating means whereby messages dispatched from the calling station are received at the receiving station and indicated at both stations, said message indicating means including parts movable in response to the dispatch of a. message, signal means at the receiving station including a message to be sent signal and a message received signal, means for energizing the message to be sent signal from the calling station, and means operable in response to movement of the indicating mechanisms at the calling and receiving stations in response to the dispatch of a message for respectively de-energizing the message to be sent signal and energizing the message received signall CHAUNCEY L. CALKINS. 

